Watch.



F. L. FRENCH.

WATCH.

APPLICATION FILED JAN. 3. 1916.

1 02,047 Patented 00b. 24, 1916.

lnvenron Frank L. French by Mad M W Arrys.

UNITED STATES PATENT OFFICE.

FRANK L. FRENCH, OF MERIDEN, NEW HAMPSHIRE.

WATCH.

Application filed January 3, 1916.

To all whom it may concern:

Be it known that I, FRANK L. FRENCH, a citizen of the United States, and resident of Meriden, New Hampshire, have invented an Improvement in Watches, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

This invention relates to an improvement in watches and has particular reference to anovel means for securing the outer end of the usual balance or hair-spring to the watch plate, cock or bridge. At present the usual construction is to attach the inner or relatively movable end of the hairspring to the staff of the balance wheel by a collet or other suitable means. The other end of the hair-spring, passing between the depending pins or curbs on the regulator which serve to check its activity at this point, is securely affixed to a stud rigidly mounted in an arm projecting from the watch plate, cook or bridge. Disadvantages have long appeared in this construction in that extreme delicacy. of manipulation is necessitated properly to position and affix the hair-spring end to this stud. One of the greatest difliculties is the liability and tendency of the tenuous spring to become distorted. This generally occurs when the hair-spring end is being affixed to the stud.

Such distortion is very difficult to perceive and to overcome. It usually manifests itself by throwing the plane of the coiled hair-spring out of its correct position in parallelism with the plane of the balance wheel. The accuracy of the time-pulsations of the balance wheel is thus adversely affected. and the efficiency of the mechanism as a time-keeper diminishes correspondingly. In thisnew construction, the relatively fixed or outer end of the hair-spring is provided with a novel anchorage to the bridge or cock or other portion of the watch plate to which it is usual to aflix the spring end. This novel anchorage provides a plurality of adjustable positions for a universal ball joint. The ball has the spring end secured thereto and after all adjustments are made, so far as a skilled watchmaker may accurately effect them, the ball is permitted unrestricted movement to assume a position in obedience to any tension of the spring end so that all distortion thereof is Specification of Letters Patent.

Patented Oct. 24, 1916.

Serial No. 69,750.

automatically obviated. The ball is then retentively held in such position.

An object of this invention is to afiford a novel anchorage of the outer end of the hairspring of a timepiece which substantially automatically compensates for and removes hair-spring distortion.

Another object is to afl'ord a plurality of adjustments for the outer end of a hairspring.

Other objects of the invention will more fully appear from the following description and the accompanying drawings and will be pointed out in the annexed claims.

In the drawings, Figure 1 is an enlarged plan view of the cock of a watch embodying the novel features of this invention; 2 is a cross sectional view through the novel adjustable member on the line 22 of Fig. 1; Fig. 3 is an enlarged View in elevation of the novel ball and stud.

This invention is disclosed as applied to a watch having the cock construction; but, obviously, it may be employed in the wellknown bridge or other watch plate construc tion and in other chronometers or timekeepers employing a hair or balance spring to cause the balance to pulsate under influence of a main-spring, weight or other media.

The cock 1 has mounted thereon the ring base 2 of the regulator from which projects the arm 3, the end of which is reciprocally movable above the usual graduated scale not necessary here to be shown. The upper end of the staff 4 of the balance wheel 5 is pivoted, as is common, in the center of the circle inscribed by thering base 2 of the regulator. The opposite end of the staif is pivoted in the usual manner. This pivotally mounted balance wheel has'secured to its staff t, the inner or relatively movable end 6 of the hair spring 7 of the common coiled type. It is to be understood that springs of other types may be employed, this embodiment being selected for purposes of illustration. Coiled about itself and the staff 4 of the balance wheel 5, the spring 7 terminates in the outer or relatively fixed end 8 which is secured indirectly to the cock by this novel anchorage, a preferred embodiment of which is shown.

The head 9 projects from the cock and in an aperture therethrough the preferably cylindrical block 10 is positioned. The

block 10, movable in the head 9, is held against rotatory or vertical movement by means of the set screw 11 received in threaded engagement in a suitable aperture 12 in the side of the head 9. Upon turning in of the set screw, the point thereof bears against the block and secures the same against movement.

A threaded aperture 13 is made through the major portion of the block 10 and is eccentric with relation thereto. This threaded aperture 18 preferably terminates in a ball cup 1% substantially hemispherical in form. The ball 15 is positioned and is freely movable therein. The screw 16, re-

ceived in threaded engagement in the aperture 13, is preferably reduced at its lower end. This lower end may be a flat surface but in this embodiment is a surface 17 concaved to fit a small portion of the top surface of the ball. The frictional contact therefore between the screw end and the ball is much less than the contact between the ball and its cup 14, in order that the turning down of the screw 16 will not turn the ball in its top but will only effect its retention in its assumed position The ball is thus held against movement in the block 10 by the turning down ofthe screw 16. A stud 18 is preferably rigidly affixed to the ball and, adjacent its lower end,is transversely slotted to receive the end 8 of the hair-spring which is retained therein by the pin 19. The upper or ball endportion of the stud is reduced and extends through the aperture 20 of the block 10. This aperture 20 is but slightly larger in diameter than the springengaging portion of the stud as the stud ball is dropped into position through the aperture 13. The aperture 20, being larger in diameter than the stud 18, freeplay is afforded to the reduced portion of the stud in a circle having a radius sufficiently large to assure the desired adjustability of the stud. The arm 21 projectsfrom the ring base 2 of the regulator and depending therefrom are the usual curb pins 22. The hair-spring passes between the curb pins and its activity is checked at this point through limitation of the effective length of the hair-spring.

The use of this novel construction not only permits of greater rapidity in the assembling of the parts associated with the balance, but also insures maximum accuracy in the proper positioning and retention of the outer end of the hair-spring. In assembling these parts, the stud ball is inserted through the aperture 13 of the block so that the ball rests in the cup while the stud projects through the aperture 20. The screw 16 is turned down; the hair-spring end is then pinned in the stud slot. The fit of the block in the head permits its adjustment in the plane of the vertical while the eccentricity of the support of the ball stud permits its adjustment in the plane of the horizontal. These two adjustments are retained by means of the set screw. The usual anchoring of the outer end of the hair-spring with respect to what is known in this art as the isochronal point of the balance spring is thus afforded by these adjustments. As frequently occurs under the manipulation of even the most skilful watchmakers, a hairspring is twisted, entailing a torsional tension communicated substantially throughout the whole hair-spring with consequent inaccuracies in the time pulsations of the balance wheel. Such distortions, ofttimes imperceptible, in the case of the fine watch springs, are extremely difficult to overcome. In this device, the stud ball functions similarly to a universal joint. When the adjustments in the vertical and horizontal planes are made, the stud through its ball mounting automatically assumes a position requisite to take up any torsional strain in the hair-spring. And, when the ball stud has automatically assumed such position, the screw 16 may be turned down and the stud is then rigidly held in this position which neutralizes and removes all spring distortion. By means of the eccentricity of the stud ball mounting in the cock extension, a wide range of adjustment of the balance spring in the horizontal plane is assured. This adjustment thus permits the anchoring of this spring end in a plurality of positions of varying radii from the center of the staff to which the other end of the balance spring is secured.

Thewhole device is simple, efficient and durable. Not only is the correct positioning of the hair or balance spring made more easy of accomplishment but the time-element of construction cost is greatly reduced as the skilled artisan is not compelled repeatedly to adjust the balance spring to assure the obviation of spring distortion.

Having fully described my invention, what I claim as new and desire to seoure'by Letters Patent is:

1. In a horological instrument, a balance wheel, and a balance springsecured at one end to the staff of said balance whe el and anchored at its opposite end to a stationary portion of the instrument by means of a universally movable connection.

2'. In a horological instrument, a balance wheel, a balance spring secured at one end to the staff of said balance wheel and an adjustable anchor for its opposite end comprising an eccentric stud rotarily mounted in a stationary portion of the frame and connected to the spring by a rotatable instrumentality.

8. In a horological instrument, a frame having a cock provided with an extension, a balance wheel having its stafi' mounted in the cock, and a balancespring secured at one end to the staff of the balance wheel and having its opposite end connected to a universally movable instrumentality eccentrically mounted in the cock extension.

4. In a horological instrument, a frame having a cock provided with an extension, a balance Wheel having its staff mounted in the cock, and a balance spring secured at one end to the staff of the balance Wheel and having its opposite end connected to a universally movable instrumentality eccentrically mounted in the cock extension and adapted to be rotarily and vertically adjusted.

5. In a horological instrument, a balance Wheel, a balance spring secured at one end to the staff of said balance Wheel and an adjustable anchor for its opposite end comprising an eccentric stud rotarily mounted in a stationary portion of the frame, said stud mounting being vertically adjustable.

6. In a horological instrument, a balance Wheel, a balance spring secured at one end to the staff of said balance Wheel and connected at its opposite end to a ball movably positioned in a stationary portion of the frame of said instrument and means operable to retain said ball in fixed position.

7. In a horological instrument, a balance Wheel, a balance spring secured at one end to the staff of said balance Wheel and connected at its opposite end to a ball, a supporting member mounted in a stationary portion of the frame of said instrument and rotarily and vertically adjustable therein, an

eccentric ball support in said member to hold said ball in movable position and means for securing said supporting member and said ball in relatively immovable position.

8. In a horological instrument, a balance Wheel, a balance spring secured atone end to the staif of said balance Wheel and means for adjustably connecting the opposite end to astationary portion of the frame of said instrument comprising a supporting member mounted in said stationary portion and rotarily and vertically adjustable therein, said member being eocentrically apertured, a ball seat formed by a constricted portion of said aperture, a ball movably supported in said seat, a depending stud on said ball projecting through said aperture, means for securing said opposite end to said stud and means for retaining said supporting member and said ball in relatively fixed position.

In testimony whereof, I have signed my name to this specification.

FRANK L. FRENCH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

